1. Field of the Invention
This invention relates to an apparatus for installing sliders on a gapped slide fastener chain. More specifically, this invention relates to an apparatus which draws the tape from a supply, installs sliders and then cuts the chain to the desired length according to the frequency of gaps in the chain supply. Still more specifically, the invention relates to an apparatus which installs sliders and cuts slider chain and handles the chain automatically, carefully avoiding tearing or otherwise destroying it.
2. Description of the Related Art Including Information Disclosed Under .sctn..sctn.1.97-1.99
The prior art includes apparatus for applying sliders to gapped slide fastener chain and then cutting it to a desired length to make individual fly pieces, pocket zippers and the like. An example is shown in U.S. Pat. No. 4,131,993, which issued Jan. 2, 1979 to Anthony Azzara. While this patent does not disclose in detail the measuring and cutting apparatus but is more intent on the handling of the slider chain and the sliders, the apparatus embodying that invention includes means which abruptly stop the advancement of the chain when it reaches the desired zipper length away from the cutter. More accurately, the Azzara apparatus includes a finger which, when activated, ""feels" along the row of zipper teeth as the chain advances and inserts itself up into the gap when the gap arrives at the finger. An air cylinder driver having grip means engaging the leading end of the chain is then abruptly stopped.
Frequently, in the past, because of the force with which the grips pulled the chain, the cloth tapes of the individual stringers have been torn when the finger abruptly stopped the advancement of the chain. For this reason apparatuses of the prior art were provided with stop means so that the metal frame of the machine stopped the grips from pulling farther once the zipper had been drawn to its selected length. The positioning of the stop was a critical matter and was arduously set to coincide with the engagement of the finger in the trailing end of the gap. Even so, tapes were frequently torn during the slidering.